[anarchodev]

You could register it with a voip number. This doesn't entirely mitigate the problem, but at least you'd have more digital control over what happens to that number (and can pretty much be sure you won't lose it unless you want to).

If you already have it registered to a "real" number on your cell phone, there are processes for porting that number to google voice.

[ossguy]

Or to a service like https://jmp.chat/ that allows you to signup anonymously.